Hi.
I'm integrating Sin[t] / (1 + k Cos[2t]) , over 0 < k < 1, using Mathematica 4.1. I'm plotting spot values k=0.1, 0.8, 0.95 over 0
< t < 10.
This represents the acceleration of a charged particle in an alternating electric field, where k represents a particular modulation
of its effective inertia. Although the velocity plots (the integral dt) look fine (symmetrical about zero), the plots for position
(integrating velocity dt) are clearly wrong; I get a massive expression (about 20 lines!) which will not differentiate successfully
back to the original velocity expression, and they are decidedly asymmetrical about zero. The position plot ought to look like a
sinewave as k->0, but there's no resemblance.
Andrew Palfreyman